Custom braces, casts and devices and methods for designing and fabricating

ABSTRACT

A custom device and method for fabricating the custom device includes marking a body with reference points and/or other indicators. Multiple images of the body from multiple angles are then obtained. The images are used to determine the contours of the body and the other markings are located and used to design the custom device. The custom device can be fabricated as a single piece structure or in multiple pieces that are assembled to complete the custom device.

CROSS REFERENCE TO RELATED PATENT APPLICATIONS

This patent application claims priority to U.S. Provisional PatentApplication No. 61/112,751, “BRACE AND CAST” filed on Nov. 9, 2008, U.S.Provisional Patent Application Ser. No. 61/168,183, “ORTHOPEDIC BRACES”filed in Apr. 9, 2009, U.S. Provisional Patent Application No.61/185,781, “BESPOKE FRACTURE BRACE” filed in Jun. 10, 2009, andProvisional Patent Application Ser. No. 61/244,749, “BESPOKE SCOLIOTICBRACE” filed Sep. 22, 2009, which are hereby incorporated by reference.

BACKGROUND

There are various types of braces and casts that are used to protect aportion of a body during recovery. Braces are used to limit the movementof a joint and are useful in preventing injury or allowing a joint toheal by preventing movement correlating with the injury. Common bracesare elastic which are made of stretch materials or hinged which includesome hard components. Elastic braces are frequently made from wovenmaterials such as cotton, Lycra, nylon or other blends that provideexceptional breathability and wearing comfort. These braces conform tothe elbow, wrist, leg and knee providing a natural freedom of movement.Braces are typically off the shelf items that are secured to thepatient's body with straps. The brace can have pads or other cushioningwhich are placed between the patient's body and the more rigid bracestructures. Flexible off the shelf braces offer inexpensive modalitiesfor restriction of motion and added support of targeted body parts.However, the use of flexible materials and generic sizing limits theamount of control that the off the shelf brace can provide. For a givenindividual the “off the shelf” braces offer limited conformability. Theaxis of rotation is not accurately placed relative to the native jointaxes and is less useful for clinical range of motion bracing situationsthat demand greater accuracy in position, conformation, and control ofmotion.

Hinged braces usually offer greater support and stability than elasticor neoprene braces. Hinged braces are a subset of range of motionbraces. For the rehabilitation or treatment of many diarthrodial jointssuch as the knee, and elbow, motion is required early after injury,surgery or treatment to achieve a good clinical and functional result.Motion braces provide support to the injured joints while allowing forcontrolled motion in the proper planes with restriction of motionestablished by the health care provider. Without early motion, stiffnessresults with reduction in the long term range of motion and suboptimalclinical results. Hinged knee braces are examples of dynamic braces thatmove in order to provide increased support of knee joints following aninjury or after surgery. Hinged knee braces are used for treatment ofligamentous injuries within the knee or on a perioperative basis. Theyare most frequently used for the treatment of anterior cruciate ligamentinjuries and medial collateral ligament injury in the knee. These bracesare also used in a protective basis by athletes post injury and on aprophylactic basis such as football linemen, who wear the braces on aroutine basis for protection. Rehabilitative removable knee braces arealso available as range of motion braces. These braces have hingesincorporated into the brace that can specify and limit the degrees ofmotion in both flexion and extension. These can also be locked into fullextension with a “drop lock” mechanism. These range of motion braces areused frequently in a trauma or reconstructive setting in which the rangeof motion must be advanced in a controlled setting. Other dynamicsplints offer additional stress applied to the joint to achieveincreased motion in the setting of joint contractures. These bracesapply and additional force at the extremes of motion to assist instretching out the joint.

In contrast to a brace or a splint, a cast is typically acircumferential device used to immobilize and protect a limb or bodypart. An orthopedic cast is a circumferential shell, frequently madefrom plaster or fiberglass, encasing a limb or, in some cases, largeportions of the body to hold a broken bone or bones in place to allowhealing. Upper extremity casts are those which encase the arm, wrist,and/or hand. A long arm cast encases the arm from the hand to about 2inches below the arm pit, leaving the fingers and thumbs free. A shortarm cast, in contrast, stops just below the elbow. Both varieties may,depending on the injury and the doctor's decision, include one or morefingers or the thumb, in which case it is called a finger spica or thumbspica cast. Lower extremity casts are classified similarly, with a castencasing both the foot and the leg to the thigh being called a long legcast, while one covering only the foot and the lower leg below the kneeis called a short leg cast. A walking heel may be applied, or a canvas,leather or rubber cast shoe provided to the patient who is expected towalk on the immobilized limb during convalescence (referred to as beingweight bearing). Where the patient is not to walk on the injured limb,crutches or a wheelchair may be provided. The sole of a leg cast mayalso be extended to the tip of the toes, if providing a toeplate. Thisaddition may be made to offer support to and stabilize the metatarsalsand to protect the toes from additional trauma. This is a commontreatment for a broken foot. In some cases, a cast may include the upperand lower arm and the elbow, but leaves the wrist and hand free, or theupper and lower leg and the knee, leaving the foot and ankle free. Sucha cast may be called a cylinder cast, or may simply be called a long armor long leg cast.

Orthopedics casts are typically single use, non removable devices thatare circumferentially applied to the patient and are not intended to beremoved by the patient. Typically, any removal of the cast disrupts theconformity of the underlying cotton layer and leads to the replacementof the device. Immobilization devices in which the structural componentsare non circumferential are referred to as splints. These typicallyapply rigidity to a portion of the body part but allow motion, expansionor adjustment in other planes.

Casts are typically applied by physician or cast technician in layers.The body part which will receive the cast is initially covered with athin woven cotton layer or stockinette. The part is then overwrappedwith thin loose cotton wrap such as Webril that is applied in layers. Anattempt is made to apply the cotton as uniformly as possible as anyfolds or imperfection can be a source of future skin breakdown once thehard outer shell is applied. Typically greater amounts of the cottonpadding layer are applied over the terminal regions for the cast. Bonyprominences also receive additional padding. Once the padding isapplied, the body part is wrapped in either plaster of fiberglass. Thesematerials are self setting and are activated by immersing in water priorto wrapping around the body part. Casts are circumferential devices andthe plaster/fiberglass is applied as a wrap around the body part. Thephysician then applies a mold to the cast in an attempt to make the castconform and support the body part in the critical planes. For example inthe treatment of a fracture, typically a 3 point mold is applied in theplane of likely collapse or deformation of the fracture, to preventdisplacement. As the cast is circumferential, hoop stresses tend toexpand the cast dimensions in the planes orthogonal to the mold. Controlof the casting depends on the skill of the practitioner, the amount ofpadding applied, the amount of tension on the materials and theappropriate molding of the cast during the setting process. Once thecast has set, the cast may be trimmed and additional padding may beapplied to the edges if necessary to address sharp edges.

Imperfect application of the cast is associated with multiplecomplications including skin breakdown, discomfort, emergency roomvisits, compartment syndromes, loss of fixation or fracture reduction,malunion of fractures, need for surgical intervention, nerve injury,vascular injury. Revision of casts with removal and application of newcasts is a frequent occurrence and is associated with significant costand patient morbidity.

Body casts, which cover the trunk of the body and in some cases the neckup to or including the head or one or more limbs, are rarely used todayfor adults, but continue to be used commonly for the treatment ofpediatric conditions. A body cast encases the trunk of the patient'sbody, and may have sections that extend over the shoulders. The bodycast is usually referred to as a body jacket. A cast which includes thetrunk of the body and one or more limbs and a cast which includes the“trunk” of the arm and one or more fingers or the thumb are called aspica cast. For example, a shoulder spica cast includes the trunk of thebody and one arm, usually to the wrist or hand. Shoulder spica casts areused less frequently today, having been replaced with specializedsplints and slings which allow early mobility of the injury so as toavoid joint stiffness after healing. A hip spica cast includes the trunkof the body and one or more legs. A hip spica cast which covers only oneleg to the ankle or foot may be referred to as a single hip spica, whileone which covers both legs is called a double hip spica. Aone-and-a-half hip spica cast encases one leg to the ankle or foot andthe other to just above the knee. The extent to which the hip spicacovers the trunk depends greatly on the injury and the surgeon. Forexample, the spica cast may extend only to the navel, allowing mobilityof the spine and the possibility of walking with the aid of crutches, orit may extend to the rib cage or even to the armpits in some rare cases.Hip spica casts were formerly common in reducing femoral fractures, buttoday they are used commonly for the treatment of pediatric hipconditions. In some cases, a hip spica cast may only extend down one ormore legs to above the knee. Such casts, called pantaloon casts, areused to immobilize an injured lumbar spine or pelvis, in which case thetrunk portion of the cast usually extends to the armpits.

Body casts are typically applied with use of a special frame and the useof multiple technicians or physicians. The patients may require sedationif adults. Body casts or hip spica casts applied to pediatric patientsusually require general anesthesia and the casts are applied in theoperating room. The body and hip spica casts are typically worn forextended duration of 6 to 12 weeks. Excessive cost and morbidity isassociated with the need to replace the device. Hygiene is a difficultproblem for pediatric spica casts as soilage of the brace is a frequentoccurrence. The need for a general anesthetic to replace the cast is astrong disincentive to change the cast for anything other than a medicalreason.

Other body casts which were used to protect an injured spine or as partof the treatment for a spinal deformity such as scoliosis include theMinerva cast and Risser cast. The Minerva cast includes the trunk of thebody (sometimes extending down only so far as the rib cage) as well asthe patient's head, with openings provided for the patient's face, ears,and usually the top of the head and hair. The Risser cast was similar,extending from the patient's hips to the neck and sometimes includingpart of the head.

Casts are frequently made from plaster, encasing the limb and/or body.Plaster bandages consist of a cotton bandage that has been impregnatedwith plaster of paris, which hardens after it has been made wet.Alternatively, bandages made of synthetic materials are often used incasts. For example, casts are often made of knitted fiberglass bandagesimpregnated with polyurethane, sometimes bandages of thermoplastic.These synthetic material casts are lighter and dry much faster thanplaster casts.

Because the casts are applied directly to the patient's body, they havea custom fit. In contrast, most braces for common medical injuries orconditions are off the shelf items that are adjusted to fit the patient.For more severe injuries, chronic conditions or perioperativeimmobilization, greater brace control and conformity is required. Thesepatients require the use of custom braces that are frequently producedby specialists such as prosthetists and orthotists. These specialiststypically either take a mold of the patient from which they can producea positive model of the patient. Around this positive mold, theprosthetist can then wrap materials and construct a custom device. Theamounts of padding and reinforcement are based on the clinicalexperience of the orthotist and the “art” of brace manufacturing. Whencustom prosthetics, braces and orthotics are designed, medicalpractitioners frequently rely on their hands to feel the patient's softtissue and bone structure. The practitioners identify bony protuberancesthat they feel under the tissue and mark these locations as landmarksreference points that they can then use to create the custom device forthe body. The practitioners work on an iterative basis with the patientand the models of the patient to create a brace that conforms to thepatient yet has the proper padding and support necessary for itsclinical use.

There are many limitations to the traditional methods of braceproduction. The entire process is very labor intensive and inefficient.The limitations of the method of sizing and manufacture have limited theend product. Manufacturing restrictions have limited the choice ofdesigns, and the functionality of the end product. The custom devicesare labor intensive and they are limited in geometric complexity. Thecustom devices can also be highly inaccurate since they are hand madeand may only vaguely represents the patient's body. The hand madeprocess also does not allow for special adjustments to the customdevice, which may include clearances, or custom windows for tenderspots, rashes, birthmarks, moles, nipples, stitches, bruises, or otherareas on the skin that may require special clearance or avoidance. Whatis needed is an improved system and method for designing braces that aremore accurately fitted to the patient, thinner, stronger, morecomfortable and selectively flexible.

SUMMARY OF THE INVENTION

The present invention is directed towards a process for fabricating acustom brace, cast or device based upon scan data from a patient. In apreferred embodiment a photogrammetry process is used in which thesurface data for a patient is obtained from a plurality of photographsof the patient. In order to accurately measure the surface of thepatient, reference points can be applied to the patient's skin invarious different ways. The surface should have at least twelve welldistributed reference points visible in each photograph and at leasttwenty reference points for an entire surface of an object. Morereference points will result in a more accurate measurement of theobject. The marks can be dots formed by ink, stickers, or other markingsplaced directly on the patient or on a form fitting cover such as astockinette worn by the patient. In an embodiment, the cloth of the formfitting covering can be printed with the dots, textured pads or a gridof intersecting lines so that the patient will have a set of referencepoints as soon as the covering is worn by the patient. In yet anotherembodiment, a light projector can be used to project a pattern of lightonto the patient. The pattern of light can be an array of spot points, agrid of intersecting lines or any other pattern that allows images ofpoints on the patient to be detected. The light on the patient serves asthe markings can be white or colored light markers that are projectedonto the patient with a projector. Multiple projectors or mirrors may benecessary to project the light onto all required surfaces of thepatient.

In addition to reference points for obtaining the surface contours ofthe patient's body surface, the doctor or practitioner can also markareas of the patient's body to indicate the location of other featuresof the brace. For example, markings can indicate the end edge(s) of thebrace, padding areas, boney prominences, sensitive areas of the skin,holes, windows, pathologic sites (fracture or surgical sitelocalization), underlying anatomy (ex spinous processes and spinealignment) recessed areas where the brace should not be made preciselyto the contour of the patient and other features to be formed in thebrace. The markings can be made directly on the patient or on the formfitting cover worn by the patient. Like the reference points, theadditional markings must provide a clear visual contrast. The markingscan be coded by color or in another manner to indicate the type offeature to be formed at the markings. The different codings can also beused to indicate the degree or amount of deformation in an identifiedregion, type of window, or other brace feature. The markings can be athree dimensional object(s) that provide additional information. Forexample, a rod, an arrow or other object marker can indicate an axis ofrotation of a joint or other features.

After the patient has been marked, the portion of the patient's bodythat is in need of a cast or brace is placed in front of one or morestill or video cameras. The cameras can face one or more sides of thepatient's body and can be spaced apart from each other by a knowndistance. In some embodiments, a set of cameras can be arranged aroundthe patient so that a complete set of still images or photographs of thebody around a circumference can be taken. In a preferred embodiment, thecameras are arranged in groups of two cameras. The two cameras can bemounted on a bracket that spaces the cameras apart from each other. Thetwo cameras are aimed in the same general direction towards the patientor limb of the patient but offset by an angle. In a preferredembodiment, the camera lenses can be parallel to each other in a firstplane and angled towards each other in a second plane. The separationand angle allow the two cameras to each take a picture that includes thesame portions of the patient's body but from slightly different angles.The reference points on the body are triangulated from the pictures toobtain the surface contours. If photographs around the entire patientare needed, three or four groups of cameras can be arranged around anddirected towards the patient. The cameras can be coupled to a singleswitch which causes all of the cameras to be actuated simultaneously.The cameras can also be coupled to a flash mechanism. The flash for onecamera can be triggered by the shutter of one camera being actuated. Theother cameras aimed at the patient can include light sensors cause theirshutters to actuate in response to the flash of light. Thus, theactuation of the first camera will immediately cause all other camerasto be actuated. Since all pictures are taken in a fraction of a second,the body can be placed in front or between the cameras and there isnormally no need to immobilize the patient or hold the body or limbstill for an extended period of time.

This fast image capture feature is particularly important for pediatricor veterinary medical devices such as pediatric spica casts orveterinary braces. It can be very difficult to keep an infant or ananimal steady for other types of scanning processes. For most childrenand animals casting and bracing is a traumatic experience associatedwith significant pain and morbidity. Both application and removal ofcasts and braces is associated with discomfort. For many applicationsthe children and animals require either sedation or anesthesia forapplication of the casts. For example hip spica casts most frequentlyare applied with the patient in an induced sleep in the operating room.

Capturing a three dimensional image of a child's anatomy requires thatthe child be held immobile during the duration of the scan. Otherwisethe child would require sedation. For most pediatric applications, onlyphotogrammetry will offer near instantaneous three dimensional imagecapture. Combining with markings and photogrammetry, children canundergo virtual fittings for braces while minimizing the need forsedation or anesthesia and reducing the trauma of the experience.Because many infants have a substantial amount of baby fat, the markingof the infant may be the most efficient means for identifying thelocations of the underlying anatomy. Common applications for thistechnology include but are not limited to: pediatric spica casts, Pavlikbrace, clubfoot casting, metartus adductus casting, Blounts diseasecasting/bracing, ankle foot orthosis, pediatric ankle casts, pediatricwalking casts, spine-TLSO braces, halo body cast, cervical collar,torticollis bracing and other medical devices. By obtaining data fromimages, there is no need to keep the infant or animal still for anextended period of time.

In another embodiment, a single 3-D camera can simultaneously capturemultiple off axis images via a single camera. The single camera maycapture multiple images on a single frame of film. The multiple imagescan be used to capture the 3-D image. It is also possible to takemultiple images of a patient with a single camera that is moved aroundthe patient to capture multiple images at different angles if thepatient remains very still. A single camera can also be coupled to alens system that can capture images of the patient from suitable anglesand positions.

In order to get an accurate surface position, each of the referencepoints on the body must be visible in two or more photographs or images.The images are analyzed by a computer surface reconstruction program.The program triangulates the reference points through photogrammetryalso known as digital image correlation to determine a surface geometryof the body. In addition to the reference points, additional features ofthe device as marked on the patient are also shown in the images andvisible to the CAD program operator. The features can include edges ofthe brace or device, holes, pads, windows, hinges, different materialsand other features. The system operator or the CAD software can identifythe features and add the features at the marked locations on the braceor device. Frequently when a brace or cast is needed, the patient issuffering from some internal injuries and additional information such asMRIs or X-rays are available. In an embodiment, the photogrammetry canbe combined with the MRI or X-ray data to identify the locations orregions that need to be accessible or the locations of bones that aresensitive to abrasion. By integrating the MRI and/or X-ray data, thedevice can be made more accurately. The use of data from the othermodalities is especially useful in identifying the axis of rotation ofthe joint accurately in all planes to render a more accurate range ofmotion brace.

In addition to the features marked in the photographs, the designer canuse the system to add additional features including ventilation holes,flexible pads, cushioning recesses, flexibility slots, etc. The designercan also specify the brace or device materials and thicknesses. In someapplications, the designer can specify a plurality of materials used inthe brace. A strong and hard material can be specified in areas thatrequire structural strength while a flexible material can be specifiedover areas that require flexibility and/or cushioning. The brace designis a data file that includes the physical dimensions of the device thathas an interior surface that matches the body contours determined by thephotogrammetry process and additional features.

In some situations, the brace or device may not match the scannedsurface data. For example, a patient may have scoliosis and may need acorrective back brace. The brace may be used to correct the curvature ofthe back to reduce the deformity. Photographs of the back can be takento obtain the surface data. However, rather than designing a back bracethat uses the detected spine location, the back data can be modified tohelp straighten the back. In this embodiment, the software can be usedto design a back brace that is straighter than the measured back. Thesystem can obtain measurements for the overall length and curvature ofthe spine and the operator can adjust the brace design to be straighter.In one embodiment for the sizing of a back brace, the physician can markthe spinous processes of the scoliotic patient. The curvature of theback and location of the spinous processes is then captured byphotogrammetry. The provider can then correct the brace morphometry toadjust the curve reference points to provide the corrective moldedbrace. The actual difference(s) between the brace and the normal backposition can be specified by the patient's doctor.

In addition to the scanned surface data and device features, the CADsystem can also design flexibility and ventilation holes into thedevice. The designer can select one or more materials for the device andthe CAD system can know the mechanical properties of these materials.The operator can then input the flexibility characteristics which caninclude flexibility in one rotational or bending direction and morerigidity in a second rotational or bending direction. The CAD system canbe used to design holes into a device that provide a calculatedflexibility to the device. The factors that will influence theflexibility include material characteristics, material thickness, holesize, shape and orientation. In addition to providing flexibility, theholes will also provide ventilation to the patient which will alsoincrease comfort.

Additional features of the device include a modular construction. Thisis useful when used for a broken bone in a limb such as a forearm. Theinventive modular cast can be designed for a patient that can haveseveral modular sections that can be removed sequentially as the patientheals. The doctor can mark the patient to indicate the different modularsections and the modular section markings will be detected by thephotogrammetry and the brace can be designed with the marked modularsections. The brace can then be fabricated and the different modules canbe secured to each other with a joint mechanism or any other type ofremovable fastener so that the different sections can be individuallyremoved as the patient heals. If a patient breaks an arm, the entire armmay initially be immobilized in a modular brace that extends from thefingers to the shoulder. After a first period of about 2-3 weeks theupper arm module can be removed. After a second period of about 2-3weeks, the elbow and/or thumb modules can be removed. The lower arm(short arm cast) module can be worn to support the arm until the bonesheal. Since the modules are simply removed, the cast is not destroyedand new casts are not required. This is a substantial benefit to thepatient and doctor because much less time and resources are required. Asimilar modular brace can be used for an injured hand, leg or foot. Asthe patient heals, portions of the brace can be removed to allow forcomfort, movement and ventilation.

A modular design or a design using multiple material designs can also beused for braces worn by growing children. Back braces can fit a childpatient for several months or much longer. However in order to becomfortable, the brace must be able to adapt to the growth of the child.The bones around the hips tend to grow as the child develops and withouta flexible or a modular design, the child will periodically require anentirely new brace. This growth will require refitting the patientwhenever the brace is replaced. In order to prevent or minimize thereplacement, the brace can be designed with flexible sections and/ormodular components. For example, a back brace can be designed with aflexible or elastic modular portion around the hips that allow forgrowth. When the hip module cannot accommodate the patient any longer,this modular hip section can be replaced with another hip module thatproperly fits the patient. The modular hip section can then be attachedto the rest of the brace and used until the child's growth requiresanother replacement module.

Modularity is also important in the final fitting of the patient.Specific regions of back braces frequently can be difficult to fit tothe patient. The printing or constructing a brace is costly and timeconsuming. If the brace does not fit well in a specific region, the useof modular panels allows the malfitting section of the brace to bespecifically replaced without needing to replace the entire construct.

In yet another embodiment, a brace or cast can be designed having aplurality of accessible regions. Each region can be attached to a hingeor other releasable fastener that allows the portion of the brace foraccess to the patient. This can be designed over a specific area ofinterest, for example a wound area that needs to be cleaned orperiodically checked and then protected again. By placing a number ofthese accessible regions adjacent to each other, the body can be cleanedby opening each region individually while the rest of the body is heldwithin the device. The inventive brace allows improved comfort andhygiene while still protecting the patient during the healing process.For example, medical procedures may require placing pins or otherobjects in a patient. It may be necessary to avoid contact with andallow inspection of these areas. By using an access region over theseareas, the doctor will be able to inspect the area to insure that thepatient is healing properly. The accessible region feature can also beparticularly useful for infants who will need to be cleaned regularly.The inventive brace can be designed with access to the lower torsoregions that allow the child to be cleaned. The region can be opened forcleaning and then closed after cleaning is completed. This design is asignificant improvement over casts that must be partially sawed toaccess the child for cleaning.

After the brace or device is designed, the brace design data istransmitted to a fabrication machine that constructs the brace. In anembodiment, the fabrication is rapid prototyping, rapid manufacturing,layered manufacturing, 3D printing, laser sintering, and electron beammelting (EBM), fused material deposition (FDM), CNC, etc. Thefabrication machine produces a three dimensional single or multiplepiece structure that can be plastic, metal or a mix of differentmaterials. In order to efficiently produce the described devices, it canbe desirable to simultaneously produce as many component parts aspossible. Many fabrication machines can produce parts fitting within aspecific volume in a predetermined period of time. For example, a bracecan fit around the torso of a patient and have a large space in thecenter. This brace can be made, but it will only make one device. Inorder to improve the efficiency, the brace can be designed as multiplepieces that are later fused together. Rather than making a single bracewith the large open center area, the described fabrication methods canbe used to simultaneously produce components for two or more braces thatoccupy the same specific volume. By laying out the components in anefficient production manner for fabrication by an additive materialmachine, the cost of fabrication can be significantly reduced. Thecomponents can then be assembled and fused together to form the brace.Padding and other components can be added to the brace after the braceshell has been fabricated.

The use of a photographic process has many advantages over other surfacescanning technologies. The process for transposing the locations offeatures from the patient to the brace or device is simplified becausethe doctor can apply location marks to the patient directly or on a formfitting covering. Thus, the locations of the features are much morelikely to be accurately placed on the final product. The equipment costsare also reduced because the digital cameras, computers and electronicmemory are inexpensive. The photo equipment is also portable, so it canbe easily transported to patient's location. The digital data can thenbe transmitted electronically to a fabrication machine located at aguild. Alternatively, the digital device data can be recorded onto adisk and transmitted to the fabrication machine.

The inventive custom design process is unique because it provides avirtual fitting of the brace to the patient prior to fabrication of theactual device. No other known system provides the ability to designcustom products such as braces in a virtual manner. In particular, theinventive process can detect marking placed on a body and utilize thisinformation to design the product based upon the location of the mark.

While the device has been described as a medical device, such as a braceor cast for humans, in other embodiments, it is possible to use theinventive process for other products used by humans including: customchairs, seats, saddles, athletic equipment, shoes, padding, helmets,motorcycle and bicycle seats, handlebars and hand grips, etc. Thedescribed apparatus and method can also be used for braces and casts foranimals and custom saddles for horses and equestrians.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a patient being marked by a doctor for back bracefabrication;

FIG. 2 illustrates the marked patient being photographed;

FIG. 3 illustrates a top view of a patient being photographed by aplurality of cameras;

FIG. 4 illustrates a computer displaying a digital representation of aportion of the patient;

FIG. 5 illustrates a computer displaying the design process for a backbrace;

FIG. 6 illustrates a basic back brace designed from the digitalrepresentation;

FIG. 7 illustrates a process for designing holes into the back brace;

FIG. 8 illustrates the back brace designed with the holes forventilation and/or flexibility;

FIG. 9 illustrates a back brace with flexible ventilation holes;

FIG. 10 illustrates a back brace with a flexible panel;

FIG. 11 illustrates a back brace design having horizontally alignedelongated slots for flexibility;

FIG. 12 illustrate the back brace design prior to adding the slots

FIG. 13 illustrates a virtual block of material having elongated slots;

FIG. 14 illustrates the virtual block of material with slots combinedwith the back brace design;

FIG. 15 illustrates a brace and rotational axis;

FIGS. 16-18 illustrate multiple views of a brace;

FIGS. 19-21 illustrate cross sectional views of a pad for a brace;

FIGS. 22-24 illustrate images of a leg captured at different bendingangles;

FIGS. 25-27 illustrate views of a leg brace;

FIGS. 28-29 illustrate views of a leg brace with ventilation holes;

FIGS. 30-31 illustrate brace having accessible regions;

FIG. 32-36 illustrate a modular brace; and

FIG. 37 illustrates a section of a brace used to stabilize the arm.

DETAILED DESCRIPTION

The present invention is a custom designed a cast, a brace or anotherdevice having a surface that corresponds closely to a body. The cast orbrace has an inner surface that corresponds closely to the patient'sbody and may also have an integrated construction. The inventive cast orbrace is directed towards injured backs, legs and arms or other bodyparts. The cast or brace is preferably designed by an industrialdesigner using a Computer Aided Design (CAD) computer program. Themechanical data for a patient can be obtained from photographs of thepatient's body. This body data is then digitized and input into a CADprogram that is referenced to design the cast or brace. An example of asuitable CAD program is Pro/Engineer by Parametric TechnologyCorporation. Other CAD software includes: SolidWorks by SolidWorksCorporation a subsidiary of Dassault Systèmes, S. A. For simplicity, theinventive custom brace, cast or device will be described as a backbrace, however the same processes can be used to form an arm or legbrace or any other body brace, cast or device. The brace can be a hardand strong structure that is designed to surround and support theinjured portion of the body or limb.

For example, a leg brace is created for a patient using a CAD system.The leg brace can include an upper leg, knee, lower leg, and foot andhave an interior surface that matches the mechanical dimensions andsurface contours of the patient's leg. In order to accurately create aninterior surface that matches the patient's leg, the surface counters ofthe user's leg are measured. The measurement of the outer surface of theleg can be obtained in several different ways. In a preferredembodiment, a photogrammetry or image correlation technique is used toobtain the outer surface measurements which can be a set of3-dimensional coordinates that define the outer surface of the patient'sleg or any other body part.

Photogrammetry in its broadest sense reverses the photographic processby converting flat 2-dimensional images of objects back into the real3-dimensional object surface. Two or more different photographs arerequired to reconstruct a 3-dimensional object. In a perfectphotogrammetry process, two photographs would provide enough informationto perfectly reconstruct the 3-dimensional object. Unfortunately, thephotography and measuring process are generally not perfect so thereconstruction of the 3-dimensional object based upon two photos willalso have defects. The photogrammetry object measurement process can beimproved by taking more photographs and using the extra information toimprove the accuracy. The photogrammetry process will produce a set of3-dimensional coordinates representing a surface of an object from themeasurements obtained from the multiple photographs.

Photogrammetry uses the principle of triangulation, whereby intersectinglines in space are used to compute the location of a point in all three,XYZ dimensions. In an embodiment, multiple cameras are used tophotograph the leg or body part simultaneously. In order to triangulatea set of points one must also know the camera positions and aimingangles also called the “orientation” for all the pictures in the set. Aprocess called resection does the camera position and aiming anglecalculations for each camera. The cameras should also be calibrated sotheir errors can be defined and removed.

Triangulation is the principle used by photogrammetry to produce3-dimensional point measurements. By mathematically intersectingconverging lines in space, the precise location of the point can bedetermined. Photogrammetry can simultaneously measure multiple pointswith virtually no limit on the number of simultaneously triangulatedpoints. By taking pictures from at least two or more different locationsand measuring the same target in each picture a “line of sight” isdeveloped from each camera location to the target. Since the cameralocations and aiming directions are known, the lines can bemathematically intersected to produce the XYZ coordinates of eachtargeted point.

Resection is the procedure used to determine the coordinates of theobject from photograph data, based upon the camera positions and aimingdirections, also known as the orientation of the camera. Typically, allthe points that are seen and known in XYZ coordinates in the image areused to determine this orientation. For an accurate resection, you mayhave at twelve or more well-distributed points in each photograph. Ifthe XYZ coordinates of the points on the object are known, the camera'sorientation can be computed. It is important to realize that both theposition and aiming direction of the camera are needed for resection. Itis not sufficient to know only the camera's position since the cameracould be located in the same place but be aimed in any direction.Consequently, the camera's position which is defined by threecoordinates, and where it is aimed which is defined by three angularcoordinates must be known. Thus, although three values are needed todefine the X, Y and Z coordinates of a target point, six values may berequired to define a point on a picture, XYZ coordinates for position,and XYZ angles for the aiming direction.

The surface being photographed should also have a minimum number ofwell-distributed reference points that appear on each photograph and foran accurate surface measurement. The reference points can be visiblemarks placed on the object that provide a visible contrast that will beclearly shown on the photographs. There should be at least twelvewell-distributed reference points on each photograph and at least twentypoints for the entire surface of the object. The reference points shouldbe evenly distributed on the object and throughout the photograph. Thesurface of the object can be more accurately measured with a larger thenumber of reference points.

While it is possible to mark the patient's skin with ink markers, in apreferred embodiment, the patient is covered with a form fittingmaterial such as an elastic cotton tube, stockinette, leotard, bodysuit. In other embodiments, the body can be wrapped with a form fittingmaterial. In another embodiment, the body surface can be sprayed orpainted with removable materials such as a flexible plastic or rubbermaterial that conforms to the body and can marked and easily removedafter images are captured. With reference to FIG. 1, a patient 101 isillustrated wearing a body suit 103 that covers the patient's body, armsand legs.

In an embodiment, a computer program processes the photographicmeasurements to produce the final XYZ coordinates of all the measuredpoints. In order to do this, the program triangulates the target pointsand resects the pictures. The program may also calibrate the camera.Typical accuracies of the three dimensional measurements can be veryhigh under ideal operating conditions. For example, the measurements canbe accurate to 50-100 microns (0.002″ to 0.004″). However, the accuracyof a photogrammetric measurement can vary significantly since accuracydepends on several inter-related factors. Important accuracy factorsinclude: the resolution and quality of the camera, the size of theobject being measured, the number of photographs taken, and thegeometric layout of the pictures relative to the object and to eachother.

Photogrammetric measurements can be dimensionless. To scale aphotogrammetric measurement, at least one known distance is required.The known distance can be a distance marked on the object. For example,if the actual coordinates for some targeted points are known, thedistances between these points can be determined and the points can beused to scale the measurement. Another possibility is to use a fixturewith targets on it and measure the fixture along with the object.Because the distance between the targets on the fixture is known, it canbe used to scale the other measurements between reference points on theobject. Such fixtures are commonly called scale bars.

In an embodiment, the inventive method is used to make a cast or a bracefor an injured limb. A series of photos are taken of the injured limb.If the bone is broken, fracture should be reduced before the photos aretaken. The photogrammetric processing methods described above are thenused to obtain the surface coordinates of the injured limb. In order todefine common surface points on the limb, reference points can be placedon the limb. The reference points can simply be any contrasting colorpoints, patterns, shapes, objects, symbols or other optical indicatorswhich are easily visible. The reference points can be black or coloredink marks, stickers or objects or any other visible point of reference.In the preferred embodiment, the reference points are placed and evenlydistributed around the entire limb or portion of the body that the braceis being constructed for.

In addition to the reference points, the patient can also be marked todefine an edge of the brace or other features. With reference to FIG. 1,the doctor can mark the body suit 103 with a pen 105 to define thelocations of the edge of the brace. The edge marking can be one or morecontinuous lines 107 that extend around the body or limb. In otherembodiments, the edge can be defined by a series of marks that definethe edge of the brace and are connected during the brace design.Additional lines 109 can also be marked on the patient to createopenings in the brace. For example, the patient may have injured areasfrom an operation that has been closed with stitches and should not bein contact with the rigid brace. By providing an opening in the brace,the patient's stitches will not be pressed against the brace structure.In FIG. 1, the doctor has drawn a circle around this portion of thepatient's body so that the brace can be designed with a cut out for thisarea. The doctor can also make notes on the body suit 103. The doctorhas written “L6” to indicate the location of the L6 disk. The doctor hasalso marked a cross 111 at the greater trochanter of the femur anddashed lines at the shoulder blades 113. These anatomical locations areimportant in the design of the brace and are therefore marked on thebody suit 103. Because photogrammetry uses photographs, the digitalpictures will record all of the lines or other markings.

With reference to FIG. 2, photographs of the patient are taken with aplurality of digital cameras 121. In this example, the cameras 121 aremounted on a bracket 123 and horizontally separated by a known distance.The cameras 121 have the same horizontal position and the lens can be inthe same plane and angled inward towards each other. The angle of thelenses can be between about 5 to 45 degrees. The distances between thepatient 101 and the cameras 121 are also known. The two cameras 121 canbe actuated simultaneously so that the two or more photographs willrepresent the patient 101 in the same position. In order to get the bodycontour information, pictures are taken of the patient 101 wearing themarked body suit 103 from various angles around the entire circumferenceso that all surfaces of the body that will be covered by the brace. Eachphotograph should include at least twelve of the reference points. Byprocessing the photographs and triangulating the reference points andother lines and markings in the photographs, the coordinatesrepresenting the body surface can be obtained.

With reference to FIG. 3, a top view of a camera 121 system used tophotograph the patient 101 and body suit 103 is illustrated. In anembodiment, an apparatus that includes a plurality of cameras 121 thatare mounted on brackets 123 and positioned around an open space can beused to photography the patient 101. The cameras 121 are pointed intowards the patient 101 and arranged in groups of two cameras 121. Thecameras 121 can be mounted on brackets 123 that hold the cameras so theyare generally pointing in the same direction but angled slightly towardseach other. The cameras 121 can be positioned with the lenseshorizontally aligned, but rotated slightly about a vertical axis, so thecamera 121 lenses are not parallel. This angle allows the cameras 121 toanalyze the difference in the surfaces so that a 3-dimensionalrepresentation is generated, much as it is with human stereoscopicvision.

In this example, four groups of cameras 121 are mounted around thepatient 101 with each group having two cameras 121. Thus, eight photoseach from different angles are taken of the patient 101. The picturestaken by the cameras 121 together cover the entirety of the torso. Thecamera 121 positions can be moved depending upon the area of interest.In the illustration, the cameras 121 may be configured to collect datafor a back brace. However, if a leg brace is being made, the cameras 121can be lowered to a position around the leg.

An actuator can be coupled to each of the cameras 121 and used to causeall of the cameras to photograph the limb simultaneously. Alternatively,the camera 121 pairs can be synchronized to all take picturessimultaneously to capture the images of the object at the same time.Since the shutter speed is typically just a fraction of a second, thereis no need to keep the patient 101 absolutely still for an extendedperiod of time. In other embodiments, a single camera can be used tocapture multiple images of the patient. In this embodiment, the cameracan capture multiple images simultaneously or in a short period of time.The camera can have multiple lenses each capturing a different image.Alternatively, the patient can move relative to the camera. By rotatingthe patient or rotating the camera about the patient and taking multiplephotographs, a single camera can capture multiple images that can beused to obtain the surface topography and other marker data.

As discussed above, the photographs are processed and used to generatethree dimensional data that accurately describes the outer surface ofthe patient 101. The three dimensional data is then used to design andfabricate the brace or cast. Because the surface data is very accurate,the brace or cast will have a custom fit that accounts for all detectedsurface contours. In addition to the custom fit interior surface, theedges or brace features are also clearly defined by the edge or featuremarkings and can be used to assist in the design of the brace or cast.

In some cases, the physical condition of the patient is such that thephotogrammetry images will not result in an accurate brace. For example,if a patient has injured a limb, the area of injury can be swollen.Thus, any photographs of the limb will result in a scan data that ismuch larger than the unswollen limb. In an embodiment if the patient hasan intact limb that is similar to the damaged limb, the intact limb canbe photographed and the surface data obtained from the intact limb canbe reversed in a mirror manner to create the required data for a bracefor the damaged limb. The brace can be designed and fabricated so thatwhen the swelling goes down, the brace will be ready for the patient.

Photogrammetry also has various benefits over other types of surfacescanning methods including optical and laser scanning because it canalso be used to detect markings placed on the patient by a doctor whichcan be used to indicate special portions of a body or the brace. Forexample, a doctor can draw on the patient to demark any number of notesthat they will reference later in the custom device process. Thesemarking may indicate: boundaries of the custom prosthetic/orthotic,areas of bony protuberances, folds of adipose tissue, specific referencevertebrae, sensitive areas on the body (rashes, birthmarks, moles, etc)to be avoided, areas that will require enhanced ventilation, clearanceareas around joints to allow unencumbered motion, setup notes, referenceboundaries for ‘shims’ which will later add additional pressure withinthe brace and various other information. The body markings can becolored points, lines or symbols, textured markers or other codes thatare used to identify the different types of reference points on thepatient. For example, a patient may be marked with a first color toindicate a desired boundary of the brace or cast. The patient can alsobe marked with a second color or textured marker to indicate a bonyprotuberance or sensitive areas. Since the bony protuberances, orunderlying bony anatomy are areas prone to skin breakdown, the brace canhave special features over these areas to avoid abrasion or damage tothese areas. For example, during the design process, the operator canreduce the brace over the areas of the patient's body marked as bonyanatomy. An example is the placement of the brace over the regions ofthe scapula. The scapula and its borders can be palpated manually butare difficult to determine based on surface morphology. The brace mustaccommodate for the scapula to function properly. In the techniques thelocation of the edges or body of the scapula is marked on the patientand the body of the brace will accommodate the bony edges with custompadding or relief in the brace contour.

The brace will require pads to be comfortable to the patient. Thelocations of the pads can be marked on the patient as described above.For example, a pad location and shape can be indicated with a codedmarking in the shape of the pad. The CAD system will detect the padmarking and be able to fabricate a pad that matches the designatedshape. During the fabrication process, the pads can be fabricated from asoft elastic material in a range of thicknesses and firmnesses. Forexample, the CAD data can be used to cut the pads from a sheet stock ofpad material. The CAD system can also design the brace to accommodatethe pads. For example, the brace can be designed and fabricated withrecesses formed at the coded and marked areas or other attachmentmechanisms. Since the patient surface data is used to form both thebrace and the pads, they will fit together very accurately. If there areventilation holes designed into the brace over a pad location, the padcan also be designed with ventilation holes that is aligned with theventilation hole in the brace.

When the brace is fitted to the patient, the doctor will have aplurality of pads and will be able to select the best pad thickness forthe patient. Because the brace can be made of a strong and durablematerial, the pads can be worn with use of the brace and may need to bereplaced periodically. The doctor can have additional pads fabricatedfrom the brace data. Additional pads can also be made using additivemanufacturing processes such that the pads have an outer surface that isconforming to the brace and an inner surface that is conforming to thepatient's anatomy in areas with complex surface geometry such as bonyprominences such as the iliac crest.

In other embodiments, the coded marking can be a pattern, symbol, atextured pad, bar code, 3-D objects or other indicators. Because thesecameras use the photographic image for their data input, the codedmarkings or topography on the patient can be identified by thebrace/cast design software. The inventive process may be able todistinguish different color codings as well as different pad textures.The textures can include grooves, etched patterns, convex or concavesurfaces, etc. Each texture may represent a different feature of thebrace at the marker location. The detection system software mayautomatically detect and identify the coded color or texture. Thesoftware can then automatically design the requested feature of thebrace associated with the coded color or texture was positioned on thepatient. The additional markings will be transferred to the digitalrepresentation of the patient and be used to help design the brace orcast.

The process by which the scanned body data is used to design a brace isillustrated in FIGS. 4-8. FIG. 4 illustrates a scanned image of a humantorso 201 on a CAD screen 221. The contours of the torso 201 areaccurately measured and the additional markings that were placed on thepatient are also illustrated on the scan data. In this example, thedoctor has drawn a cross 211 of the patient's greater trochanter of thefemur so the brace is designed with extra space in this area formovement of the leg. Line markings 207 indicate the desired boundariesof the brace and line 209 indicates a hole in a side of the brace. Thenotation “L6” is also visible from the photogrammetry scan data.

With reference to FIG. 5, the line 207 representing the edge of thebrace is being highlighted. The line 209 representing a hole to beformed in the brace has been highlighted by the brace designer. In thisembodiment, a mouse controlled cursor 215 is used to highlight thelines. In other embodiments, the designer can select click on the lineto highlight the entire line. In this example, the darker linerepresents the portions of the line to be removed from the brace.However, any other visual markings can be used to identify the portionsof the line to be removed.

In some situations, the brace or device may not perfectly match thescanned surface data of the patient. For example, the designer can alsoaccount for the marked cross 211 representing the location of thegreater trochanter of the femur bone. The marking will be indicated onthe images captured during photogrammetry and the cross may be adesignated symbol indicating the location of the greater trochanter. Thesoftware can then adjust the design of the brace over the greatertrochanter by expanding this portion of the brace.

In another example, a patient may have scoliosis and may need acorrective back brace that changes the normal posture of the patient.The brace may be used to correct the curvature of the back to reduce thecurvature deformity. Photographs of the back can be taken to obtain thesurface data as described above. However, the actual spine position maynot be detected unless the surface shows the back bones as surfacefeatures. In order to clearly indicate the spinous processes of theback, the doctor may need to mark the location of each. The marking canbe coded to indentify the specific bones or indicate a bone that isdamaged. The markings can surround the bones, be a cross mark, or anyother mark that clearly identifies the locations of the bones. When thephotogrammetry images are processed, the locations of the spinousprocesses will be clearly indicated. The back surface and spinousprocesses locations can then be used to design the back brace.

Rather than designing a back brace that uses the detected spineposition, the back data can be modified to create a brace thatstraightens the patient's back. The designer can obtain measurements forthe overall length and curvature of the spine and the desired curvaturealteration of the brace. The difference between the brace and the normalback position can be specified by the patient's doctor. The designer canthen adjust the recorded back curvature to design a back brace that isstraighter while maintaining the desired interior volume defined by thebrace. In an embodiment, the design program can include a system foradjusting the brace design which allows for the adjustments of one partof the brace to be carried over to the other portions of the brace. Forexample, if the back data shows the photographed spinal curvature, thedesigner can manipulate the apex to reduce the curvature. Rather thanadjusting only the apex portion, the program will make similaradjustments to the surrounding portions of the brace so that thecorrective brace will properly fit the patient. For example, the bracecan be divided into many different thin horizontal sections that mayeach correspond to a different spinous process. When one section ismoved, the other sections will move to a lesser degree so that thescoliotic curvature is reduced. An algorithm may be used to scale themovement of the other sections of the brace on the CAD design. Byautomatically adjusting the different sections of the brace when onesection is moved, the brace design is simplified and accurate.

In other embodiments, the designed brace or cast can vary from thephotogrammetry measurements taken of the patient. For example, thepatient may be swollen due to trauma or inflammation. The brace designsystem can account for the swelling and allow the designer to create asmaller brace that will fit the patient after the swelling is reduced.In an embodiment, the system can use photographs of an intact limb anduse the mirror image surface data as a guide for the brace for theswollen limb. The intact limb may not be a perfect match of the damagedlimb, but in many cases it is sufficiently accurate to form a suitablebrace or cast.

In FIG. 6, the torso is illustrated with the area inside the hole line209 and torso areas outside the edges 207 removed. Although not shown,designer operating the CAD software can rotate the illustrated torso toshow any view of the brace 210. A material thickness can be added to theinterior torso surface to create the basic brace design. Because themarkings are accurately detected by the photogrammetry system, all ofthe marked edge and hole positions are transferred to the digitalrepresentation and the required brace boundaries and features areaccurately identified without having the re-examine or re-measure thepatient. The process completes the basic design of the brace 210.

In addition to patient features marked on the patient, it is alsopossible to add additional features to the brace. For example, aplurality of holes can be made in the brace 210 to provide ventilationand flexible portions of the brace. With reference to FIG. 7, the brace210 is illustrated with a set of cylinders 225 running through a portionof the brace 210. In this example, the cylinders 225 are circular incross section and define a plurality of circular holes. With referenceto FIG. 8, the designer can then remove the material that intersects thecylinders 225 from the brace 210 to produce a brace with a plurality ofholes 227.

The structural materials used to fabricate the brace are strong incompression and tension. By forming holes in the brace, ventilation aswell as selective flexibility can be added to the brace. By designingopenings into the structural material, the structural material can bendrather than be compressed or stretched which allows the brace to havebending movement. The brace designer can design the brace to control theflexibility depending upon the patient's specific needs. The brace canbe designed to control the direction(s) of flexibility, the range ofmovement, the elasticity of the movement, etc. The ability to createdetails and customized holes and vary these holes regionally in thebrace allows for control of motion in bending and torsion independentlyin different planes, and independently at each level. Articulationsbuilt into the brace allow also for controlled motion independently ateach level.

With reference to FIG. 9, a back brace 318 is illustrated having apattern of elongated holes 322, 324. The holes 322, 324 can addventilation as well as flexibility to the back brace 318. The holes 322,324 tend to add flexibility across the width of the holes 322, 324.Thus, in this example, the upper portion of the brace 318 withhorizontally oriented holes 322 will tend to allow for verticalflexibility. In contrast, the vertically oriented holes 324 around thelower portion of the brace 318 will allow for more radial flexibilityaround the brace 318. The lower brace 318 may be positioned over thehips of the patient. As the patient moves and grows this area mayrequire expansion flexibility.

With reference to FIG. 10, a back brace 418 is illustrated made of threeparts. Rather than making the brace as a single piece structure, it maybe more efficient to produce the brace in three separate parts that arelater assembled. It is also possible to make one of the panels out of adifferent material. For example, the center panel 424 may be a moreflexible material than the sides. While the side panels 422 of the backbrace 428 may need to be made of a fairly rigid material, the centerpanel 424 may not require the same strength and may be made of a moreflexible material. The center panel 424 can then be secured to the restof the brace 418 with suitable fasteners.

For example with reference to FIG. 11, a back brace 310 is illustratedhaving a plurality of elongated horizontal slots 325. The slots 325allow the brace to be vertically flexible but rigid in axial rotation.When a bending motion is applied to the brace 310, the vertical elementswill tend to compress the centers of the slots 325. However, when arotational torque is applied to the brace about the center axis, thebrace 310 will be more rigid. In the illustrated back brace 310, theholes on the front and back of the brace are elongated slots 325 thatare arranged in offset rows and columns. The slots 325 in eachhorizontal row are offset relative to the adjacent vertical rows ofslots 325. The material between the slots 325 form elongated strips thatare mostly horizontally oriented. There are short vertical strips 326that intersect the center portions of each slot 325. As discussed, thematerial is strong in compression and tension. Therefore, this designconfiguration resists torsion or axial rotation of the patient's back.However, because the horizontal strips of material are not alignedvertically, the brace 310 can bend forward and back which allows thepatient's back to bend. When the patient bends forward, the front of thebrace is compressed and the material bends so the slots 325 at the frontof the brace become shorter in height and smaller. Conversely, the backof the brace can be stretched longer and the material can bend so theslots 325 at the back of the brace become higher. In this example,because the slots 325 are wide and short, they are stiffer againsthorizontal forces while more flexible with vertical forces. In contrast,a slot that is tall and narrow will be stiffer against vertical forceswhile more flexible with horizontal forces. Thus, the flexibility of thebrace 310 can be controlled by varying the size and arrangements of theslot 325 openings.

With reference to FIG. 12, prior to adding the slots, the back brace 310design is a solid form that is rigid and does not provide anyventilation to the user as displayed on the CAD software display. Slots325 or other ventilation holes can be formed by manually adding theslots to the brace design as described above with reference to FIG. 7.Alternatively, a brace 310 with slots can also be added by combining theback brace in a more automated and time efficient manner. With referenceto FIG. 13, a block of material 327 is illustrated with preformed slots325. The designer can input the dimensions of the brace 310 and definethe center area of the brace 310 that requires the slots 325.

With reference to FIG. 14, brace 310 and the block of material 327 arevirtually combined by the CAD program and displayed on the computerscreen. The upper and lower portions of the brace 310 are illustratedwithout the slots while the center portion of the brace that requiresthe slots intersects the block 327. The designer can then remove theportions of the block 327 that is outside the brace 310 edges. Theresulting brace 310 is designed with a center portion having slots 325as illustrated in FIG. 11.

In an embodiment, the desired flexibility can be designed into the braceby varying the hole size, shape, orientation, material thickness andfabricating the brace from two more different materials that each havedifferent mechanical properties. These calculations can be integratedinto the CAD software so that by inputting the flexibility requirements,the software can compute the details of the brace design that complieswith the structural requirements. By modifying the mechanical propertiesof the brace throughout its shape, it may be inclined to bend, rotate,compress, expand or remain rigid along certain rotational directions asdesired.

In an embodiment, the brace comprises a conformal surface, a structuralcomponent shown as horizontal and vertical ‘beams’, and a ‘border’ thatsurrounds the brace and increases structural properties where desired.The horizontal beams, in this example, could compress forward, sincethere exists no vertical beams to restrict the compression. This wouldallow forward flexion. Lateral flexion, however, is restricted by thevertical beams on the sides of the brace. Rearward flexion would berestricted by the vertical border contours that extend upward along thespine of the brace.

A thinner layer that is highly perforated can be placed between thestructural components. This would offer no structural impact, but isintended to contain the tissue of the patient and prevent the skin frommoving into the slots and being pinched during compression of the slots.The ventilation holes are small (below ⅜″), thereby reducing the chanceof ‘window edema’ problems. This layer behaves as a ‘netting’ of sortsto contain the body, while not impacting the structural requirements.The holes may be designed in such a way that the surface expands orcompresses easily. This may involve holes that are elongated along thehorizontal axis, and a grid pattern that is offset (like a checkerboard,rotated 45 degrees) so that no vertical beams are created in the grid,thereby diminishing the structural properties of the surface.

Unlike previous brace technologies, this invention describes a method inwhich the mechanical properties including bending and rotationalproperties are specified by the health care professional. The pattern ofventilation is also specified. Then the computer creates the brace tomeet the mechanical and ventilation specifications while also matchingthe conforming shape of the body surface and meeting the overallgeometric constraints of the brace. The shape of brace, mechanicalproperties are chosen, perforation type or design are chosen by healthcare professional. The brace is then created in which the thickness andwidth of the structural elements are varied to meet the mechanical anddesign considerations of the brace. The brace is then produced byadditive manufacturing or any other fabrication method.

In many brace applications, the inner surface of the brace must applypressure without causing skin breakdown. Pressure points must beavoided. The highly conforming brace will minimize contact stresses andwill thus minimize the breakdown of skin. However, softer materials maybe required over contact points. In addition to minimizing window edemawith small perforation internally, with additive manufacturingtechnology, the inner surface may be constructed of laminated structuresproduced in continuity with the external exoskeleton to allow theinternal layer or layers to be more conforming. Thin deflectableconforming layers may be printed on the inner walls. In otherembodiments, completely different materials can be added to the brace.For example, in some other embodiments the brace design and fabricationcan include printed mesh or printing a foam like porous material on theinner walls that allow compression and ventilation. The inner layer orlayer will be produced by additive manufacturing with all layersproduced in continuity.

Thus, the brace can be designed as a homogeneous material or as acomposite structure of laminated layers of materials. The outer layermay be a very strong structure that functions as an exoskeleton thatprovides the required strength for the body or limb. While the innerlayers of the brace can be a combination of hard and soft materials thatare designed to promote healing of the patient. Soft compliant materialscan be used over areas that are adjacent to bones. The position of thebone may change while the patient moves. Thus, it is important for thisarea of the brace to be comfortable. In contrast, harder materials canbe used against the softer fat and muscle tissue of the body. Becausethese softer internal surfaces can be damaged or may wear out soonerthan the hard materials, they may be designed as replaceable panels orparts that snap in and out of the brace.

The breathability of the brace is another feature that makes theinventive brace more comfortable. The brace can be designed withventilation passageways that extend throughout the brace. Because thebrace is designed on a CAD system, the locations of the ventilationholes is known and can be automatically designed into any additionalpadding or panels that are placed in the brace. In some cases, the padsmay be made of a breathable material and the ventilation holes in thehard solid portions of brace may provide ventilation to a much largerinternal surface of the soft porous pad.

The brace design can also control the flexibility by combining both thevertically and horizontally orientations of the beams, a brace canfeature difference areas of flexibility from one part to another,without compromising ventilation. In an embodiment, the beams ofmaterial are curved. For example, a portion of a brace can have morehorizontally oriented beams on a first side, and more verticallyoriented on a second side. In this manner, the first side will be morelikely to compress and expand under pressure, while the second side willnot. The second side, by contrast, will more likely bend and act as apivot. If, for example, the front of the body features morehorizontally-oriented beams and the sides feature more verticallyoriented beams, then the brace would allow forward flexion, though denyany lateral flexion. At the same time, however, ventilation would beequally uniform throughout the brace. This illustrated configuration canbe applied to a back brace that allows bending forward but prevents sideto side bending. The left side can represent the front of the brace andthe right side can represent the right side of the brace. The horizontalalignment of the beams in the front and the vertical alignment of thebeams at the side allow forward rotation but prevent side to siderotation.

A basic principle of the brace invention is the asymmetric flexibilityof the brace. With reference to FIG. 15, the brace 410 is shown in termsof an XYZ coordinate system with the front of the brace facing the Xaxis, the left side facing the Y axis and the top facing the Z axis. Inthis example, the brace 410 is a back brace and the lower portion of thepatient and brace 410 are stationary. If the patient leans to the left,the brace 410 will bend clockwise about the X axis and if the patientleans to the right, the brace 410 will bend counter clockwise about theX axis. If the patient bends forward, the brace 410 will bend counterclockwise about the Y axis and bending back will cause the brace 410 torotate clockwise about the Y axis. If the patient twists to the right,the top of the brace 410 will rotate clockwise about the Z axis andtwisting to the left will cause the top of the brace 410 to rotatecounter clockwise about the Z axis. By knowing which directions toimmobilize the patient's movements, the brace 410 can be asymmetrical inbending.

With reference to FIGS. 16-18, different views of a back brace 510 areillustrated. FIG. 16 illustrates a front view of the brace 510, FIG. 17.Illustrates a side view and FIG. 18 illustrates a back view. The brace510 can be configured with horizontal beams 505 on the front section andthe front portions of the left and right sides. Because the spine shouldnot be compressed, the back of the brace 510 may include vertical beams507 while does not have vertical beams. Because the back is stiffer thanthe front, the back will tend to bend but not compress. In contrast, thefront will compress or expand in response to the bending of the back.Because the vertical beams 507 are mounted across the width of the brace510, they can prevent the brace 510 from bending from side to side.While the brace 510 has vertically and horizontally aligned beams, theseonly represent the general alignment of the beams. The beams of theactual brace will cross each other and be angled or bent to provide therequired directional strength and flexibility.

With reference to FIGS. 19-21, another feature that can be designed intothe brace is a dense grid of individually suspended contact pads 611involves each pad 611 being ‘hollow’, giving it the shape of a torroid.This allows contact ‘rings’ 615 to contact the skin, each contract pad611 can have a ventilation hole 619 at the center. The ventilation holes619 gives improved airflow to the skin. The ‘doughnut’ shape of it makeswindow edema less likely, since there are no hard edges to press againstthe skin to disturb the blood flow. And the relatively large contact pad611 area will likely increase the comfort against the skin. Air willalso flow around each of the contact pads 611, and can be evacuatedthrough a perforation pattern through the outer wall. This will increasecomfort to the user and cool the surface skin temperature.

Because each of the contact pads 611 may be created as an individualrevolved ‘cell’, it can be created so that a ‘well’ exists around eachof the pad's ‘stocks’. Beyond the ‘well’, the wall thickness grows,since the thick parts of the cells intersect adjacent cells. This allowsa relatively strong structure to be created that is flexible wheredesired (around the stocks of each pad), yet strong where desired (inbetween each stock). Both strength and compliance is met in a singlesurface. This contact point on a stalk approach distributes the skincontact over many individual points. These point contacts minimize thearea of decreased circulation by allowing blood flow to the skin betweenthe contact points. The compresses area can thus receive blood supply bydiffusive processes. This strategy minimizes the potential for largerischemic zones or areas of skin breakdown. In addition, by varying themechanical properties of the stalk that supports the contact point theamount of shear stress at the skin can be minimized. If the stalk issufficiently flexible, with motion of the skin within the brace, motionwill not occur between the contact point and the brace but instead willoccur at the level of the stalk, between the contact pads and theexoskeleton outer layer of the brace. By minimizing shear and ischemia,such a padded structure can minimize the potential for skin breakdown.

For dynamic braces, these contact pad 611 constructs can be produced asa coherent volume of attached structures, or for more dynamic braces,the contact pads 611 may be printed as discrete elements in continuitywith the outer exoskeleton and ventilation pattern, but whereby thecontact pads 611 and support structure exclusive of the exoskeleton arenot in contact. Such a construct would allow for differing motions inselect regions of the brace without any impact on the mechanicalproperties due to the contact pads.

The pads 611 illustrated in FIGS. 19-21 are part of the inner surface ofthe brace. Each pad 611 is flexible and movable in compression as wellas horizontal movement. In an embodiment, the pads 611 each have acontact portion 615 and a stem 621 that is coupled to a frame. When thepad 611 is compressed against a portion of the patient's body, forexample when the brace is worn by the patient, the contact portion 615is compressed against the stem 621 which is compressed against the frame629. The stem 621 can be much narrower than the contact portion andbendable. When the contact portion 615 of the pad 611 moveshorizontally, the stem 621 will bend in response to the pad 611movement. The stem 621 is also coupled to the frame 629 in such a waythat the stem 621 can move in a perpendicular direction relative to theplane of the frame 629. Thus, the pad 611 can move in response to anyperpendicular compression of the pad 611 against the frame of the brace.In an embodiment, a portion or the entire interior surfaces of the bracecan include the described pads 611. The pads 611 used in a brace can allbe identical or each can have a different design characteristics. Forexample, the pads 611 located over harder surfaces such as bones underthe skin can have flexible pads 611 that allow for comfortable movementof the bones and/or joins. In contract, the pads 611 that are locatedover softer areas of the body can have stiffer since the soft areas maynot require as much padding. FIG. 19 illustrates a cross section of anexample of a single pad 611 element. FIG. 20 illustrates the pad 611 indirect compression and FIG. 21 illustrates the pad 611 in diagonalcompression. In the compressed illustrations, the stem 621 bends inresponse to the pressure applied to the pad 611.

In other embodiments, different flexible pad designs can be usedincluding non-circular surfaces, different spring stems and differentventilation mechanisms. The hardness or softness of the pads can bequantified by the spring rate of the stem against the frame and thecontact area of the pad. A pad with a large contact area and a lowspring rate will be very soft. In contrast, a pad with a small contactarea and a high spring rate will be a harder pad. The equationquantifying the hardness or softness of the pads is (pad surfacearea)×(stem spring rate)=X. For example, if the pad area is 1 squareinch and the spring rate is 10 lb per inch, when the pad is compressed ¼inch into the frame, the force will be 2.5 lbs per square inch. If thepad is compressed ½ inch into the frame the force will be 5 lbs persquare inch. The dynamic hardness/softness characteristics of each ofthe pads can be individually designed into the brace. The pad areas canrange from about ¼ square inch to about 5 square inches and the springrate of the stem can range from about 0.01 lb/in to about 100 lb/in ormore.

Other features that can be added to the brace design include hinges thatallow the brace move at a joint or opened to be more easily attached tothe body and removed from the body. The hinge can be located at a jointsuch as the user's knee or elbow to enables the brace to move with theknee or elbow joint. In order to determine the proper orientation of thehinge, a series of photographs of the limb can be taken at differentjoint angles. For example with reference to FIG. 22, a first set ofphotos can be taken of the leg 791 with the knee bent with one or morecameras 121. With reference to FIG. 23, a second set of photos can betaken with a slight bend in the knee 793 and with reference to FIG. 24,a third set of photos can be taken with the knee 793 straightened. Byusing the cumulative data, the designer can determine surfacecoordinates for each leg 791 position and the most accurate location forthe hinge. The elbow or knee does not move in perfect rotation about afixed axis, however the designer can determine the closest fitrotational axis for the brace. Once the best rotational axis isdetermined, the designer can integrate a hinge into the brace design.

With reference to FIGS. 25-27, the hinges 830 can be a circularstructure that couples the upper portion 822 and lower portion 824 ofthe brace 801. In an embodiment, the upper portion 822 and lower portion824 are connected by two hinges 830 mounted on opposite sides of thebrace 801 and define an axis of rotation. The hinges 830 can includebearing structure that minimizes the rotating friction of the hinge 830and allows for smooth movement of the upper portion 822 and lowerportion 824. The bearing 830 can include an inner race and an outerrace. The inner race can have a bearing surface that extends around theouter diameter and the outer race can have a bearing surface whichextends around the outer diameter of the race. Bearings such as ballbearings, roller bearings, etc are mounted between the races. Thebearing materials can be metal, ceramic, plastic, etc. With the surfacecoordinates, a designer can integrate the bearing structures into thedesign of the brace.

In order to insert and remote the limb, the brace 801 can have anopening mechanism(s) that allows the user to easily insert and removethe limb. For example, the brace 801 may be split along the length anddivided into two or more portions that are coupled together. In order toinsert the limb, the entire brace can be open and after the limb isinserted, the brace portions 8220, 824 can be secured around the limb.In an embodiment, the brace 801 can have a hinge 826 on one side and alatch mechanism 828 on the opposite side. The latch 828 can be releasedso the brace 801 can be opened. In order for the opening hinge(s) tofunction properly, it must be aligned along the length of the brace 801.More specifically, if the brace 801 includes a hinge 826 for the elbowor knee, the hinges 826 coupled to the upper section 822 and lowersection 824 must be aligned so the brace can be opened. In anembodiment, the opening hinges 826 are aligned when the upper section822 and lower section 824 of the brace 801 are aligned. Thus, the brace801 may only be open when the upper section 822 and lower section 824are aligned.

When the outer surface coordinates have been obtained, the innersurfaces of the brace can be designed to match the outer surfaces of thelimb. This provides a brace or cast that perfectly matches the injuredlimb. The matching surfaces allow the brace or cast to have a moreaccurate and comfortable fit. The designer can also determine athickness of the brace that is sufficient to support and protect thelimb. The designer can split the brace into two pieces along the lengthso that the brace can be opened and the patient can insert or remove thelimb.

With reference to FIGS. 25-27, the system can also determine the bestlocations for hinges 826 that extend along the length of the brace 801.Because the outer surface is not straight, the hinge 826 may only bemounted at the outermost portions of the brace 801 along a straightline. In an embodiment, the computer design software will locate apreferred hinge 826 location that may extend along the longest line thatis within a short distance of a straight line that is at the back of theleg. This configuration allows the latches to be mounted on the front ofthe leg which allows the brace or cast to be more easily removed orattached. For example, the longest straight line at the back of a legbrace may be at the back of the calf area of the leg. The design systemwill integrate a hinge along a line that extends along the back of thecalf area that is within a predetermined distance, such as ½ to 1 inch,from the line. The design system can fill in the gap between the hingeand the curvature of the brace with filler material. A closure mechanismcan be coupled to the opposite side of the brace which can be a latch,clamp, ratchet, or other closure mechanism. The closure mechanism may beadjustable so that the interior volume of the brace can be variable. Theclosure mechanism can be clamped tight so that if the limb gets smallerdue to atrophy, the brace can also be made smaller to maintain a properfit. The brace can also be expanded if the limb gets larger due toincreased muscle size or swelling.

In an embodiment, the arm or leg brace includes an upper and a lowerportion that move about knee hinges or bearings relative to each other.In this embodiment, the opening mechanism can include an upper and lowerhinge that are each coupled to the upper and lower portions of the brace801. The designer can align the upper portion 822 and lower portion 824of the brace 801 with a straight line 818 as shown in FIG. 25 and theninsert the straight hinge 826 at the intersections of the brace 801 andthe straight line 818 as shown in FIG. 26. In this example, the hinge826 has two sections that are axially aligned. Thus, the upper portion822 and the lower portion 824 must be aligned to open the brace 801.Along the opposite side of the brace 801, the design system can insertone or more coupling mechanisms 828 that will hold the brace together asshown in as shown in FIG. 27.

Another problem with existing casts is that they do not allow air tocirculate against the limb. This can be uncomfortable because the limbis not easily cleaned and the dead skin is not removed. In order toallow for some air circulation against the limb, the brace or cast canbe designed with ventilation holes that can be distributed over thesurface of the brace. Many small holes 903 can be distributed over theentire cast or brace 901 and extend between the inner and outer surfacesas shown in FIG. 28. This allows the brace or cast 901 to bestructurally very strong, but still allow for air to circulate againstthe skin. The inner surface may also have channels or grooves in thesurface that allow air to flow against the skin.

In other embodiments, larger holes 914 may be formed in the brace orcast 912 as shown in FIG. 29. Since these areas under these larger holes914 will not provide support or protection, the larger holes can bepositioned over less critical areas of the brace. For example, a legbrace may be used to protect the knee. Thus, the ventilation holesshould not be located in areas that the brace is intended to protect. Inaddition to functional purposes, the holes or any other ornamental,identification, or other features can be built into the brace or castdesign.

With reference to FIG. 30, in an embodiment, the brace 901 can have aplurality of accessible regions 902, 904, 906. The access regions 902,904, 906 can be large or small depending upon the injury and patient.The different regions 902, 904, 906 may be marked on the patient priorto photogrammetry. Each access region 902, 904, 906 can be attached to ahinge 912 or other releasable fastener that allows the individualportions of the patient covered by the brace 901 to be accessed. Theaccess regions 902, 904, 906 can be strategically placed over a specificarea of interest, for example a wound area that needs to be cleaned orperiodically checked. In other embodiments, the access regions 902, 904,906 can also extend along the entire length of the brace 901. The entirelimb or body area covered by the brace 901 can be accessed for cleaning,inspection, removal of stitches 951 or other reasons by opening eachregion 902, 904, 906 individually while the rest of the limb or body isprotected and immobilized by the brace 901. With reference to FIG. 31,in another embodiment, the brace 920 can have an individual accessregion 922 and the rest of the upper portion 924 of the brace can becoupled together.

With reference to FIGS. 32-37, in an embodiment, the brace 930 can be amodular design that can have a modular construction with modularsections that can be completely removed from the brace 911. This designcan be useful for a broken limb bones such as a forearm. Casts are wellknown in the medical art. When a bone is broken, the bones can be set toreduce the size of the fracture and a cast is placed around the hand,lower arm and upper arm. As the arm heals, the casts are removed andreplaced with smaller casts. A patient can go through several castreplacements depending upon the type of break. This can be very timeconsuming because each cast must be sawed off and a new shorter castmust be constructed over the arm or leg. Also as discussed, theapplication and removal of casts with a cast saw can be very traumaticto children who may need to be sedated during these procedures.

In an embodiment, a modular brace 930 can be designed for a patient thatcan have several modular sections including: an upper arm 940, cuff 942,elbow 938, lower forearm 932, upper forearm 934 and thumb spica 936. Thesections can be removed sequentially as the patient heals. The patientcan be marked at the junctions between the different module sections.The markings are detected by the photogrammetry process and thedifferent module sections are designed into the brace 930. Becausex-rays are normally taken of broken bones, this x-ray data can be viewedwith the photogrammetry images and the brace 930 can be designed withthe required structural integrity to protect the arm at the damagedareas of the body. The brace 930 is designed as described and themodular sections can be secured to each adjacent section by removablefastener such as screws 915 or any other type of couplings that areformed in the brace or attached to the modular sections.

With reference to FIG. 32, if a patient breaks an arm, the entire armmay initially be immobilized with a brace 930 that extends from thefingers to the shoulder. With reference to FIG. 33, after a first periodthe cuff 942 can be removed from the upper arm module 940. This allowsthe elbow to flex after a period of isolation. If the cuff 942 is hingedto the upper arm module 940, the coupling can be opened. Alternatively,the cuff 942 can be coupled to the upper arm module 940 with Velcro andmay be un-velcro-ed to remove the cuff 942. With reference to FIG. 34,after a second period, the entire upper arm module 940 can be removedwhen appropriate for treatment to allow the elbow flexion. An elbowmodule 938 still exists which surrounds the elbow and allows flexion,but does not allow for rotation.

With reference to FIG. 35, the elbow module 938 is removed leaving a‘short arm’ cast for the remainder of the treatment. This upper forearm934 can be coupled to the lower forearm 932 with a hinge 912 and may beopened temporarily for cleaning of the skin and inspection, though itwill close in order to keep the arm stabilized during the treatment.With reference to FIG. 36, the ‘thumb spica’ 936 may be removed at anytime during the treatment, allowing motion for the thumb. Finally, withreference to FIG. 37, lower forearm module 932 of the brace 930 mayremain as a ‘splint’ that may be held in place by a Velcro strap ifneeded after treatment for additional stability and safety.

In other embodiments, a similar brace can be made for an injured hand,foot or leg. For example, when a patient injures a hand, the entire handmay initially need to be placed in a modular brace that includesdifferent modules for the wrist, palm, fingers and thumb. The brace mayalso include access portions. The doctor can mark the area that isinjured as well as the desired locations for each of the module seamsand access location. The brace can then be designed and fabricated. Thebrace is then assembled with all of the modules and any required pads.As the hand heals, the individual modules can be removed from the braceand the patient can regain use of the hand. Eventually, only the damagedfinger may need to be in a brace until the patient has fully recovered.Because the hand has many small components, it can be difficult to makeand remove traditional hand casts. The inventive process greatlysimplifies the recovery process because only one brace is required andthe modules are simply removed as the patient heals.

Removing the modules at the designated time periods can be veryimportant to the healing process. A joint that is left immobile forextended periods of time can become very stiff. Thus, it is important tomake the joints active as soon as possible. The lower arm module 925 cancontinue to be worn to support the patient's arm until the injured bonescompletely heal. The inventive brace has many benefits over traditionalcases. Since the modules are removed, new braces are not required. Sincethe braces modules are removable, the doctor can inspect the limb andthe patient can clean the limb if necessary. The patient does not needto remain at the hospital after the injured limb is marked andphotographed. A substantial amount of time is saved when each section isremoved compared to having to periodically remove and replace the cast.Additional padding can be inserted into the brace if the limb shrinksdue to atrophy. Finally, if the patient breaks the limb again, thecustom modular brace may be reused if the limb has not changedsignificantly. In addition to being the proper dimensions, the brace orcast must also be strong enough for the required use. An ankle brace orwalking cast may be required to support the user's weight and impactwhile running or jumping and an arm brace or cast must be able towithstand the normal use forces. In an embodiment, the strength of thebrace or cast is determined by the geometry of the brace or castcomponents and the materials used to fabricate the components. Suitablematerials include high strength plastics such as high strengthpolyamides metals, alloys and composites such as carbon fiber in anepoxy binder.

In another embodiment, markings on the skin can determine areas forpadding of bony contours or areas for adding additional padding overtime to maintain contour. Using this system, conforming pads can beprinted by the same process to fit within the confines of “fittedregions” within the inner walls of the cast. An array of conformingsurface pads of progressive thicknesses can be produced and provided tothe health care provider with the initial cast. The inner conformingpads can be made of a softer flexible material that can be produced byadditive manufacturing techniques.

The inner pads can have porosity that matches the ventilation holes ofthe outer exoskeleton for improved ventilation. The inner pads can havelocking devices manufactured into the pads such that they snap into thecorrect location with the correct orientation. Alternatively, anadhesive can be used to attach the pads to the brace. Because both thepads and brace are custom made, they may be marked with locationsindicators that can be text, color coding or symbols indicating whereand possibly how the pad and brace should be attached to each other. Forexample, the text on the pad may state, “attach this pad to the upperback section of the brace by attaching the connector to hole A in thepad.”

As the body heals, the lack of movement can result in atrophy whichcauses the body to shrink. Thus, the first set of pads may be the thin.When the brace or cast with the original thin no longer fits properly,the thin pads are removed and replaced with thicker pads. The array ofconforming pads can include the different thicknesses that are expectedto be needed. Since the digital design for the pads is stored,additional pads can be fabricated from the stored pad designs.

The CAD system can be used to design the load-bearing member of thebrace or cast. In general, the cast or brace will be much stronger thanrequired by the user. In an alternative embodiment, the designer caninput the weight and activity level of the user into the CAD system andthe required strength can then calculate based upon expected loads. TheCAD system can then design a load bearing structure that will be able tosupport the load requirements.

The medical device can be designed as a single or multiple piecestructure that is designed to be fabricated simultaneously through arapid prototyping process. Alternatively, the medical device can bedesigned as a multiple piece structure that is assembled before use.This multiple piece construction can be more efficient in terms offabrication. Rather than forming the brace as a single piece that is notspace efficient, the brace can be fabricated from a plurality of flattersections that are later assembled. When a brace is designed with a largeopen center volume, the fabrication machines produce the brace but thecenter volume is empty. The fabrication machines can operate at the samespeed and cost if the center volume is empty or filled with otherstructures. Thus, by designing the brace as a plurality of flatsections, the components for one or more braces can be fabricatedsimultaneously in a more efficient manner. After the components arefabricated, they can be assembled to form the brace, for example, asillustrated in FIG. 10.

Once the design is finalized, the design data produced by the CAD systemcan be used to fabricate the brace or cast. Because the information forthe brace or cast are in a digital format, the brace or cast can befabricated anywhere. In a preferred embodiment, the fabrication takesplace locally, so the patient can receive the brace or cast as quicklyas possible. Alternatively, the patient can be in a remote location andthe brace or cast design information can easily be transmittedelectronically to a fabricator located in a more industrial area. Thebrace or cast can then be fabricated using the design data and shippedto the patient located in the remote rural location.

In the preferred embodiment, the brace or cast is fabricated through arapid prototyping process that uses an energy beam directed at a bath ofliquid or powdered material. Similar fabrication processes are known asadditive manufacturing, rapid manufacturing, layered manufacturing, 3Dprinting, selective laser sintering (SLS), fused deposition modeling(FDM), stereo lithography (SLA), electron beam melting (EBM) and othermethods. These fabrication processes use an energy beam that isdeflected across the material and causes the exposed material to harden.Another possible manufacturing process is fused material deposition(FDM).

The cross section design data is used by the fabrication machine toconstruct the main or entire brace or cast assembly in a sequentialseries of layers. As each layer of material is hardened, the completedportion of the custom cast, brace or device component is movedvertically into the bath and the next cross section layer is formed andfused to the adjacent formed layer. When all layers are formed, thecustom cast, brace or device component is completed. The structure canbe a single piece or assembly of multiple pieces may be required tocomplete the device. Because the fabrication process can be preciselycontrolled to create sliding surfaces, even the hinged portions can befabricated simultaneously with the other portions of the cast or brace.

In an embodiment, the brace or cast is fabricated as a single integratedstructure so that the finished product is complete. As discussed above,the moving components of the inventive brace or cast can be coupled to aknee or elbow or opening hinge having rotating components. For example,the opening hinge may have bearing components that have require rodsthat rotate within holes. The rapid prototyping method cansimultaneously produce the rods and corresponding holes.

In other embodiments, additional components can be added to the cast orbrace so that the components do not slide against the same material. Inan embodiment, bushings or bearings can be added to the brace or cast atthe points of rotation. The bushings may be made of lubricious materialssuch as, stainless steel, ceramic, Delrin or Teflon. In otherembodiments, bearings are used. The bearings may be sealed units withroller, needle, ball bearings or any other type of bearing. The bearingmaterial may be ceramic, metal or plastic. Known mechanisms may be usedto retain the bushings and/or bearings between the sliding surfaces.

In another embodiment, the surface data of the body or injured limb canbe obtained through another scanning process and input into the CADprogram. For example, the body or limb can be scanned with athree-dimensional optical scanner. The body or limb must be scanned frommultiple sides to obtain a full three dimensional digital image. Thescanner creates a data set of geometric measurements for many points onthe surface of the body or limb. The accuracy and detail of the threedimensional digital image is improved by taking more measurements of thebody or limb. Suitable handheld laser scanners include the FastSCANsystem by Polhemus and the Handyscan 3D system by Handyscan. Thedrawbacks of optical scanners is that they may not only detect thesurface of the body and not the markings placed on the patient. Also thescanning can take a substantial amount of time because, the opticalbeams may need to be moved over the entire body of the patient. Thepatient must also remain very still during the scanning process. Asdiscussed, this stillness can be extremely difficult without sedation ofinfants or animals. Because of these drawbacks, photogrammetry is thepreferred method for obtaining the surface and marking data for thepatient.

The scan data is converted into a usable surface file that can be readby the CAD program. More specifically, the surface data from scan of thebody or limb may be referenced in order to extrapolate the shape of thebody or limb through a reconstruction process. The reconstructionprocess uses an algorithm that connects, the adjacent points, known as apoint cloud, with lines from the scanned body or limb data to constructa continuous surface from many small polygon shapes that form a polygonmodel. The data produced by the reconstruction process is a continuousthree dimensional digital representation that closely matches thesurface of the body or limb. An example of the software used to performthe scanner data reconstruction process is Geomagic Studio by GeoMagicand Pro Scan Tools which is a plug in module for Pro/Engineer byParametric Technology Corporation. The reconstruction surface file forthe body or limb is input into the CAD program for the cast or bracedesign.

In an embodiment, the components or an articulating brace are fabricatedsimultaneously using a rapid prototyping machine. While the parts caneasily be fabricated simultaneously, it can be difficult to create partssuch as the knee joints mounted on opposite sides of the brace. In anembodiment, the knee joint has a ball bearing construction that can beinstalled as an integrated or modular mechanism. Rather than fabricatingthe races and the ball bearings simultaneously, the joint can befabricated with just the bearing races. After fabrication, the bearingscan be inserted between the race components. The bearings provide asmooth sliding mechanism and also tighten the fit between the slidingcomponents. If the bearings wear out, they can be replaced so the legbrace can be repaired. Alternatively, the bearings can be a modulardesign that can be removed and replaced when worn out. In yet anotherembodiment, the joint can be a sliding modular bushing that can also bereplaced when it has worn out.

As discussed, the photogrammetry can detect other markers used toindicate additional information about the patient to the brace designerand CAD software. The axis of rotation of the knee can be determined andindicated prior to obtaining images of the knee. For example, anelongated rod or any other marker indicating an axis can be placed oneither side of the knee to indicate the axis of rotation. The rod ormarker will be detected and the CAD software will interpret this markeras indicating the axis of rotation. Alternatively, it may also bepossible to derive the axis of rotation based upon multiple images ofthe knee taken at multiple bending angles as illustrated above withreference to FIGS. 22-24. Similar markers can be used to indicate theaxis of rotation of any other joint that is needed in a custom brace ordevice.

Because the range of motion is controlled by the joint, it is possibleto limit the range of motion by using stops in the knee joint of the legbrace. In an embodiment, the stops can be variable and adjustable as thepatient heals. Initially, the range of motion can be limited to a narrowmovement. As the patient heals, the range of motion can be expandeduntil the patient regains the full range of motion for the limb and/orbody. In an embodiment, an elastic resistance mechanism can be appliedto the ends of the range of motion. Thus, the last predetermined angularmotion can be resisted by an increasing elastic spring force. Like thestops, the elastic region is variable and will normally be expanded asthe patient heals.

In an embodiment, the CAD system can include a graphical user interface(GUI) that allows the designer to easily change the appearance of thebrace or cast. The GUI may be a special, custom, proprietaryapplication, or it may simply be a CAD model that is built inside Pro/E.The GUI can have controls that allow the brace or cast to be viewed witha specific color that preferably matches the user's skin color but mayalso be any other color.

When the designer completes the designs of the brace or cast, the designdata produced by the CAD software can be used to create a unique andcustom fabricated the brace or cast. Rapid prototyping is a generalcategory of systems that uses digital design data and software tofabricate the components from various types of materials includingmetals and plastics. These machines most often use an energy beam thatis deflected across a bed of liquid or powdered material. The exposureto the energy beam causes the material to fuse together and harden.These fabrication machines are able to create all custom cast or bracecomponents.

In order to fabricate the cast or brace components with the rapidprototyping machines, the CAD design data may need to be modified. Thenormal CAD design data for a component is converted into many parallelcross sections of vector data that extend along the length of thecomponent. The data transmitted between the CAD software and thefabrication machine approximates the shape of the component crosssections through many connected triangular facets. Smaller facetsproduce a higher quality surface but require more time to calculate andcan create very larger manufacturing data sets. The output of the CADdesign program can be a standard STL file that is an export option,similar to a JPG export or any other file format.

The vector data for the component cross sections is read by a rapidprototyping scanner controller that converts the vector data to movementinformation which is sent to the energy beam scanhead. In a laser beamembodiment, the rapid prototyping machine includes a scanhead having twomirrors that deflect the laser beam in the X and Y coordinates over abath of liquid or powder material. The fabrication information is thenused to control the print head cross section to create each componentcross section successively. The scanhead controller reads thefabrication data and causes the print head to expose successive layersof liquid, powder, or sheet material to precise patterns of laser light.Once the layer is completely formed, the component is moved into thebath so a thin layer of the material covers the previously formed layer.The process is repeated many times with new layers formed and fused tothe previously formed layers. In an electron beam embodiment, anelectron beam is deflected over a bath of material in the X and Ycoordinates with magnetic fields. The component cross sections aresequentially formed until the component fabrication is completed.

The primary advantage to additive fabrication rapid prototyping is theability to create very complex shapes and geometric features. A lightweight and strong cast or brace can be made with a rapid prototypingmachine from plastic materials such as photopolymers. An additionalbenefit of rapid prototyping is the ability to create complex,interlinked and assembled parts in one run. In contrast, traditionalmeans used by the prior art required the individual manufacture manyparts, followed by an assembly of the parts. Thus, the assembly can addsignificant costs, even though the individual parts may themselves costvery little to produce.

The rapid prototyping process can be applied to various materialsincluding thermoplastics, photopolymers, metal powders, eutectic metals,titanium alloys and other materials. Because the inventive cast or braceis intended to be inexpensive, the preferred material is a thermoplasticmaterial. Examples of some suitable rapid prototyping machines include:laser sintering machines by EOS GmbH, electron beam sintering machinesby Arcam AB and laser stereo lithography machines and selective lasersintering machines by 3D Systems Corp. Similar fabrication processes areknown by the names: additive manufacturing, rapid manufacturing, layeredmanufacturing. 3D printing, laser sintering, electron beam melting(EBM), etc. All of these fabrication processes use a similar operatingprinciple of scanning an energized beam over a bath of material tosolidify a precise pattern of the material to form each layer until theentire component is complete.

Another possible fabrication process is fused material deposition (FDM).FDM works on an “additive” principle by laying down material in layers.A plastic filament or metal wire is unwound from a coil and suppliesmaterial to an extrusion nozzle which can turn on and off the flow. Thenozzle is heated to melt the material and can be moved in bothhorizontal and vertical directions by a numerically controlledmechanism, directly controlled by CAD software. In a similar manner tostereolithography, the model is built up from layers as the plastichardens immediately after extrusion from the nozzle.

The inventive brace or cast can be fabricated in a sequential process.It an embodiment, a patient's limb or body part can be marked withreference points and photographed. The photos are processed and thereference points are triangulated to create the 3-D surface data filefor the limb. The photos may include data for the limb in variouspositions and the photos may be used to determine a location of themoving knee or elbow. The designer can add additional features such asthe opening hinge, the closure mechanisms, ornamental features, a kneeor elbow rotational mechanism to the brace or cast and the final designis then converted into an electronic data file. The brace or cast datafile is transmitted to a rapid prototyping machine which creates thebrace or cast, possibly in a single fabrication process from aphotopolymer material. Any additional components are required such asbushings, bearings or foot sole inserts, can be installed at thefabricators facilities. The completed brace or cast is then delivered tothe end user. Since digital data can be transmitted on digital media viamail, electronically via cell or satellite, the inventive processgreatly improves the design, fabrication and distribution of braces andcasts.

It will be understood that the inventive system has been described withreference to particular embodiments, however additions, deletions andchanges could be made to these embodiments without departing from thescope of the inventive system. For example, the same processes describedfor designing and fabricating a body or limb brace can also be appliedto the design and construction of: shoulder spica, hip spica, spicacasts, Pavlik brace, clubfoot casting, metartus adductus casting,Blounts disease casting/bracing, ankle foot orthosis, pediatric anklecasts, pediatric walking casts, spine-TLSO braces, halo body cast,cervical collar, torticollis bracing and other medical devices. In otherembodiments, it is possible to use the inventive process for otherproducts used by humans including: custom chairs, seats, saddles,athletic equipment, shoes, padding, helmets, motorcycle and bicycleseats, handlebars and hand grips, etc. The described apparatus andmethod can also be used for braces and casts for animals and customsaddles for horses and equestrians. The described apparatus and methodcan also be used for other applications including: automobile bodyrepair and repair or reconstruction of other objects that require thereproduction of a surface contour. In an embodiment, the inventiveprocess can be used to repair or replace sculptural and speciallydesigned items such as jewelry. These items can be produced by theartist and then photographed and the digital representation can bestored. If the items are damage, lost or broken, the digital data can beused to make molds to reproduce or repair the objects. Although thecustom casts, braces and devices that have been described includevarious components, it is well understood that these components and thedescribed configuration can be modified and rearranged in various otherconfigurations.

1. A method for designing a brace comprising: creating ink markings on abody of a patient indicating a location of an edge of the brace;obtaining a plurality of digital photographs of the body and the inkmarkings; processing the digital photographs with a photogrammetryprocess or an image correlation process to obtain a digitalrepresentation of a surface of the body and the location of the edge ofthe brace; storing the digital representation of the surface of the bodyand the edge of the brace in a computer memory; and creating a designfor the brace on a computer having an outer surface, an inner surfacethat corresponds to the surface of the body and the edge of the bracethat corresponds to the ink markings.
 2. The method of claim 1 furthercomprising: covering the body with a conforming material prior tocreating the ink markings on the body.
 3. The method of claim 1 furthercomprising: creating an ink junction marking on the body indicating alocation of a junction between a first module and a second module of thebrace; and adjusting the design of the brace to incorporate the seam ofthe brace at the location indicated by the ink junction marking on thebody.
 4. The method of claim 1 further comprising: creating an ink holemarking on the body indicating a location of a hole in the brace; andadjusting the design of the brace to incorporate the hole at thelocation indicated by the ink hole marking on the body.
 5. The method ofclaim 1 further comprising: creating a sensitive area ink marking on thebody indicating a location of a sensitive area; and adjusting the designof the brace to incorporate a recessed area at the location indicated bythe sensitive area ink marking on the body.
 6. The method of claim 1further comprising: inputting flexibility characteristics of the brace;and adjusting the design of the brace to incorporate the flexibilitycharacteristics of the brace.
 7. The method of claim 1 furthercomprising: creating an ink joint marking indicating a location of ajoint on the body; determining an axis of rotation for the joint; andadjusting the design of the brace to incorporate a hinge adjacent to thejoint ink marking on the body and aligning the hinge with the axis ofrotation of the joint.
 8. A method for designing a custom devicecomprising: creating ink markings on a body of a patient indicating alocation of an edge of the device; capturing a plurality of digitalphotographs of the body and the ink markings; processing the digitalphotographs with a photogrammetry process or an image correlationprocess to obtain a digital representation of a surface of the body andthe location of the edge of the device; storing the digitalrepresentation of the surface of the body and the edge of the device ina computer memory; and creating a design for the device having an outersurface, an inner surface that corresponds to the surface of the bodyand the edge of the device that corresponds to the ink markings.
 9. Themethod of claim 8 further comprising: covering the body with aconforming material prior to creating the ink markings on the body. 10.The method of claim 8 further comprising: marking features of the customdevice with the ink markings on the body; and adjusting the design ofthe custom device to incorporate the features of the brace indicated bythe ink markings on the body; wherein the digital photographs includethe features of the custom device indicated by the ink markings on thebody.
 11. The method of claim 8 further comprising: creating an ink holemarking on the body indicating a location of a hole in the customdevice; and adjusting the design of the custom device to incorporate thehole indicated by the ink hole markings on the body.
 12. The method ofclaim 8 further comprising: creating a sensitive area ink marking on thebody indicating a location of a sensitive area; and adjusting the designof the custom device to incorporate a recessed area at the locationindicated by the sensitive area ink marking on the body.
 13. The methodof claim 8 further comprising: inputting flexibility characteristics ofthe custom device; and adjusting the design of the custom device toincorporate the flexibility characteristics of the custom device. 14.The method of claim 8 further comprising: creating an ink joint markingindicating a location of a joint on the body; determining an axis ofrotation for the joint; and adjusting the design of the custom device toincorporate a hinge adjacent to the joint ink marking on the body andaligning the hinge with the axis of rotation of the joint.
 15. A methodfor designing a custom device comprising: creating ink markings on abody of a patient indicating a location of a body structure; obtaining aplurality of digital images of the body and the pen markings; processingthe digital images with a photogrammetry process or an image correlationprocess to obtain a digital representation of a surface of the body andthe location of the body structure; storing the digital representationof the surface of the body and the location of the body structure in acomputer memory; and creating a design for the device having an outersurface, an inner surface that corresponds to the surface of the bodyand a feature of the device that corresponds to the location of the inkmarkings.
 16. The method of claim 15 further comprising: covering thebody with a conforming material prior to placing the ink markings on thebody.
 17. The method of claim 15 further comprising: creating an inkhole marking on the body indicating a location of a hole in the customdevice; and adjusting the design of the custom device to incorporate thehole at the location indicated by the ink hole marking on the body. 18.The method of claim 15 further comprising: creating a sensitive area inkmarking on the body indicating a location of a sensitive area; andadjusting the design of the custom device to incorporate a recessed areaat the location indicated by the sensitive area ink marking on the body.19. The method of claim 15 further comprising: inputting flexibilitycharacteristics of the custom device; and adjusting the design of thecustom device to incorporate the flexibility characteristics of thecustom device.
 20. The method of claim 15 further comprising: markingthe body with a coded ink marking prior to creating the design for thedevice; and identifying the coded ink marking.
 21. The method of claim20 further comprising: providing a feature of the design of the customdevice that corresponds to the identity of the coded ink marking. 22.The method of claim 20 further comprising: providing a feature of thedesign of the custom device that corresponds to the location of thecoded ink marking.